Conditioning of vattable quinoidic compounds



3 2,766,244 CONDITIONING F VATTABLE QUINOIDIC COMPOUNDS Robert E.Brouillard, Westfield, N. J., assignor to General Aniline & FilmCorporation, New York, N. Y.,

a corporation of Delaware No Drawing. Application November 13, 1953,Serial No. 392,029 14 Claims. (Cl. 260-272) The present inventionrelates to a process for conditioning water-insoluble vattable quinoidiccompounds, and more particularly, to an acid pasting procedure appliedto such compounds which provides products whose particle size, particlesize distribution, and particle surface characteristics render themexceedingly suitable for textile and other applications, as for example,dyeing, printing, padding, coloring of masses, and the like.

Water insoluble vattable organic dyestuffs are generally obtained aslarge coarse crystals or highly agglomerated amorphous masses. If thesebe applied Without modification they possess very poor applicationproperties and tinctorial values. it is therefore necessary in order todevelop fully the coloristic potential and Working properties of thedyestuffs, to so modify their nature that the particle characteristicsare rigidly controlled.

Various methods have been developed for the conditioning of waterinsoluble vattable organic dyestuffs. The most important of these isthat known as acid pasting. Such acid pasting may be accomplished by twogeneral methods. The first method involves solution of the dyestuif inconcentrated acid followed by precipitation of the dyestufi by drowningthe acid solution into water. The second method involves slurrying thedyestuif in a large volume of acid having a concentration insuflicientto effect appreciable solution, followed by diluting with water.

These two processes, although applicable to most water insolublevattable organic dyestulfs suffer from disadvantages in that theyrequire large quantities of acids which are generally of an extremelycorrosive nature. In addition to this unfavorable economic andoperational factor, the use of such volumes of acids requirescorrespondingly large pieces of equipment and poses problems inindustrial hygiene and safety, as well as an extremely serious andcostly disposal problem.

Further factors militating against the adoption of such procedures arethat the quality of the products obtained varies from run to run and isoften unsatisfactory for particular applications, and that theconcentration of dye stuffs in the final presscake is low. Low presscakeconcentrations are disadvantageous in that they result in lowercapacities, greater handling costs, and involve troublesome operationssuch as distillation or hydraulic pressing before marketable productscan be obtained.

The above disadvantages have long been recognized and proposals havebeen made to overcome them by modifying the conventional acid pastingprocedures. To this end it is suggested in U. S. Patent No. 2,334,812 todrown the acid solution of the dyestutf in water under conditionsdescribed as turbulent flow. On the other hand, U. S. Patent No.2,176,011 teaches the spraying of the acid solution into water.

While these modifications have led to improvements in specificproperties, these improvements have been ac companied by degradation inother properties. More important still is the fact that thesemodifications have failed to eliminate the basic economic, quality, andhandling problems inherent in the previous acid pasting procedures.

Suggestions have also been made with regard to the use of conditioningmethods which avoid acid pasting. One such suggestion comprises thesolution of a vattable nited States atent 2,766,244 atented Oct. 9, 1956dyestuff as the leuco compound and precipitation by oxidation. Anothersuggestion in U. S. Patent No. 2,402,167 describes the creation of smallparticles by grinding under suitable conditions. These procedures haveserious operational disadvantages and involve high manufacturing costs.When this factor is added to the fact that the dyestuffs conditioned inthis way show no advantage over those obtained by acid pasting, it ismanifest that these conditioning methods have not met with fullacceptance by the trade.

The purposes and objects of the present invetnion are constituted by theprovision of an acid pasting method for conditioning Water-insolublevattable quinoidic compounds which yields products of optimum particlecharacteristics and high presscake concentrations while avoiding theunfavorable economic, hygiene, and safety factors of previous methods,as well as the extremely serious and costly disposal problems inherentin such methods. Other objects and advantages will appear as thedescription proceeds.

The above objects are attained by the instant invention which isdirected to a process comprising milling with forces predominantlyshearing in nature a mixture in the form of a doughy kneadable masscomprising a waterinsoluble vattable quinoidic compound and from 0.5 to4 parts by weight of the compound of a strong normally liquid,non-oxidizing and non-reactive acid having a concentration ranging from68 to percent, and then diluting the milled mixture with water. Theaqueous mixture may then be filtered and washed acid free.

As strong non-oxidizing, non-reactive normally liquid acids which may beemployed in the process of this invention, there may be mentionedsulfuric, phosphoric, chlorosulfonic, chloroacetic, and loweralkylsulfonic acids such as methyl sulfonic, ethyl sulfonic and thelike. These acids will not react (i. e., oxidize, reduce, sulfonate,etc.) with the compound being milled under the conditions of thetreatment herein contemplated. The greatest economy and best results areobtained with sulfuric acid and the use of this acid is thereforepreferred. These acids are to be employed in concentrations ranging from68 to 100 percent by weight. A simple test is all that is necessary toascertain the specific concentration within this range which will giveoptimum results with the specific compound and compound to acid ratiosemployed in any particular instance.

One of the essential features of this process is the quantity of acidemployed. Such quantity should be that necessary to produce with thecompound being milled a doughy kneadable mass. Accordingly, the ratio ofvattable quinoidic compound to acid will fall within the range of 1:05to 1:4 by weight. Within this range, the particular quantity of acidwhich will produce a doughy kneadable mass could be readily determinedby experimentation in any particular instance. If the quantity is toosmall, the water-insoluble vattable quinoidic compound does not wet outcompletely. In addition the shearing characteristics are not ideal. Toogreat a quantity of acid, on the other hand, does not allow adequateshearing and leads to lumpy masses in which the acid does not contactall of the particles of the compound.

The particular apparatus used for effecting the milling of thewater-insoluble vattable quinoidic compound must be capable of exertingforces predominantly shearing in nature substantially uniformlythroughout a mass having the proportions of compound to acid statedabove. I prefer to use a Werner-Pfleiderer type of mill, but Banburymixers and others of this general class, as well as mills capable ofeffecting shearing by means of extrusion may also be employed.

The temperature at which the process is carried out is not particularlycritical so long as non-reactive conditions are maintained and may infact vary between the melting point and the boiling point of thecomposition being milled, as for example, between about to 150 C. Thereis a definite relationship between the temperature employed and the acidconcentration required to give optimum results with a particularcompound. Higher temperatures generally require lower acidconcentrations. For practical reasons, I prefer to operate in thetemperature range of about 20 to 50 C. since unjacketed equipment maythus be employed. The milling time under shear is also dependent on:other factors and may range from as little as about minutes to as muchas 5 hours or more, the shorter periods being obviously preferred wherepossible.

The procedure of this invention is suitable for the conditioning of anyWater-insoluble vattable quinoidic compound. The term vattable isemployed in its accepted sense, namely the ability of the compound to bevetted or solubilized with reducing agents such as hydrosulfurous acidsor the salts thereof, caustic alkali and sodium hydrosulfite,sulfoxyl-compounds and the like, to its leuco form. The meaning of theterm quinoidic is intended and is to be understood as being exclusive ofcompounds having an indigoid structure. These compounds treated inaccordance with this invention may contain inert substituents which donot interfere with the attainment of applicants desired results,

As examples of water-insoluble, vattable quinoidic dyestuflis which maybe conditioned in accordance with the process of this invention, theremay be mentioned:

(1) Acylamino anthraquino-nes such as Algol Yellow WG (C. I. 1126),Helio Fast Yellow 6GL (C. I. 1127), Algol Pink R (C. I. 1128), AlgolScarlet G (C. I. 1129), Algol Violet B (C. I 1130),

1,4-di-benzoylaminoanthraquinone,

1,5-di-benzoylaminoanthraquinone Algol Yellow 36 (C. I. 1139),

l-(p-diphenoylamino)-anthraquinone [U. S. 2,277,527],

Acylaminoanthraquinones of U. S. Patent Nos. 2,143,717, 2,183,873,2,190,751, 2,000,348 and 2,228,455 and the like.

(2) Anthanthrones and their substitution products, such asDichloroanthanthrones,

Dibromoanthanthrones,

Mixed chloro-bromoanthanthrones,

Dihydroxyanthanthrones,

Monocyano and dicyanoanthanthrones,

Monoaminoanthanthrones,

Mononitroanthanthrones,

Dianthronyl thioethers,

Dihalogenated-dianthronyl thioethers,

Alkoxylated anthanthnones,

Condensation products of halogenated anthanthrones and1-aminoanthraquinone-Z-aldehydes,

Condensation products of dihalogenated anthanthrones withl-aminoanthraquinone on the :one hand, and 4- aminoanthraquinone on theother hand,

Condensation products of anthanthrone with l-n-aphthylamines orl-aminoanthr-aquinones,

and the like.

Specific examples of va-t dyestufis within these categories areanthanthrone, dibromoanthanthrone, dichloroanthanthrone and theanthanthrones described in U. S. Patent Nos. 1,801,709, 1,803,757,1,803,758, 1,805,912, 1,805,913, 1,820,019, 1,822,045, 1,835,396,1,849,426, 1,876,972, 1,876,973, 1,877,315, 1,880,440, 1,897,427,2,191,685, (see Examples 8 to 12 inclusive), 2,320,694, and the like.

(3) Anthraquinone acridones such as Benzo [b] naphth [2,3-h1acridine-5,8,16 (15 H)-trione 6,10,12-trichloronaphth [2,3-c]acridine-5,8,14 (13 H)- tn'one,

[as-areal;

5 l-anthraquinonylamino) nap'hth [2,3-c] acridine- 5,8,14 (13 H)-trione,6-(2-anthraquinonylamino) naphth [2,3-01 acridine- 5,8,14 (13 H)-trione,

lO-chloronaphth [2,3-c] acridine-S,8,l4 (l3 H)-trione,

10,-12-dibrom'onaphth [2,3-c] acridine-5,8,14 (13 H)- trione,

10,12-dibromo-1l-chloronaphth [2,3-c1 acridine-5,8,14

(l3 H)-trione,

ll-chloronaphth [2,3-c] acridine-5,8,14 (13 H) -trionc,

lO-methoxynaphth [2,3-c] acridine-5,8,14 (13 H)-trione,

9-methoxynaphth [2,3-0] acridine-5,8,14 {13 H)-trione,

6-methylnaph-th [2,3-c] acridine-5,8,l4 (l3 H)trione,

IO-methyinaphth [2,3-cl acridine-5,8,14 (13 H)-.trione,

Benzo [b] naphth [2,3-h] acridine-5,8,16 (l5 H)-trione,

10,10'-methylene bis (naphth [2,3-c1 acridine-5,8,l4 (l3 H)-trioue)Napht h [2,3-b] acridine-7,12,14 (5 H)-trione,

Benzo [a] naphth [2,3-i1 acridine-9,14,16 (7 H)-trione,

The anthraquinone acridones described in U. S. Patent Nos. 1,709,993,1,781,238, 1,785,801, 1,804,538, 1,833,770, 1,837,649, 1,840,383,1,848,073, 1,848,074, 1,850,482, 1,851,082, 1,851,085, 1,855,295,1,857,232, 2,180,419, 2,185,140, 2,204,232, 2,238,209, 2,242,411,2,267,139,

and the like.

(4) Anthraquinone azines, such as Indanthrene Blue R and RS (C. I.1106), V

Indanthrene Blue 36 (C. I. 1109),

Indanthrene Blue 5G (C. I. 1111),

Indanthrene Blue GCD (C. I. 1113),

Indanthrene Blue GC (C. I. 1115),

Indanthrene Green BB (C. I. 1116),

N,N8-dimethy1-1,2,1,2'-anthraquinone azine and the anthraquinone azinesdescribed in U. S. Patent Nos. 1,877,146, 1,877,946, and the like.

(5) Anthraquinone oxazoles, such as1-amino-2-anthraquinoyl-2',3'-anthraquinone oxazole,

1 aminQ-Z-anthraquiuoyl-u-mono-chloro-2,3'-anthraquinone oxazole,

1 amino-Z-anthraquinonyl-4-ethoxy-2,3' anthraquinone oxazole,

4-aminoanthraquinone-1,2-(N) -phenyl oxazole,

Anthraquiuone-1,2-isoxazole and its 5 nitro derivative,

Anthraquinone 1,2,5,6-di-is'oxazole,

1,4 diamino-2-anthraquinonyl-2,3-anthraquinone oxazole,

1 amino 4 nitro-2-anthraquinony1-2,3'-anthraquinone oxazole,

The anthraquinone oxazoles disclosed in United States Letters PatentNos. 1,822,972, 2,123,834, 2,147,569, 2,147,570, 2,168,174, 2,174,072,2,175,803, 2,206,127, 2,206,128, 2,244,655, 2,245,520, and the like.

(6) Anthraquinone thiazoles, such as C-methyl-2,1-anthraquinonethiazole, C-phenyl-Z,I-anthraquinone thiazole,4-benzoylamino-C-phenyl-2-l-anthraquinone thiazole,C-phenyl-1,2-anthraquinone thiazole,4'-dirnethylamino-C-phenyl-1,2-anthraquinone thiazole,6-amino-C-phenylanthraquinone-1,2-thiazole,1,2,5,6-anthraquinone-C-diphenyldithiazole,1,2,8,7-anthraquinone-C-diphenyldithiazole,

(7) Dibenzanthrones (including isodi'benzanthrones), and their nitro-,halogenated, amino-, and alkoxylated derivatives such as IndanthreneGreen B (C. I. 1102), Indanthrene Violet RT (C. I. 1100), IndanthreneDark Blue BO (C. I. 1099), Indanthrene Violet R (C. I. 1103),Indanthrene Brilliant Green B (C. I. 1101), the halogenateddibenzanthrones described in U. S. Patent Nos. 1,003,268, 1,589,303,1,791,215, 1,925,410, 1,982,312, 1,982,313, and 2,232,700, the aminoderivatives described in U. S. Patent Nos. 1,742,317, and 2,107,656, theamides described in U. S. Patent Nos. 1,856,203, 1,895,101 and1,994,136, diinethoxydibenzanthrone (Jade Green),dinaphthdibenzanthrone, and the like.

(8) Anthraquinone carbazoles, such as4-acetylamino-4'-methyl-1,Z-anthraquinone carbazole,

4-acetylamino2'-bromo-4-methyl-1,2-anthraquinone carbazole,

-benzoylamino-4-methyl-1,2-anthraquinone carbazole,

4-m-bromobenzoylamino-4'-methyl 1,2 anthraquinone carbazole,

2,3,2',3-dianthraquinone carbazole and its N-methyb,

and the (9) Dipyrazolanthrone and its halogenated, nitro, alkyl, andcycloalkyl derivatives, i. e.,

Dichlorodipyrazoianthrone, Dibromodipyrnzolanthrone,Dichloro-N,N'-dirnethyldipyrazolanthrone,Dichloro-N,1-I-diethyldipyrazolanthrone, Nitrodipyrazolanthrone,Nitro-N,N-dimetl1y1dipyrazolanthrone, N,N'-dimethyidipyrazolanthrone,N,N-diethyldipyrazolanthrone, N-cyclohexyl-N'-methyldipyrazolanthrone,N-cyclohexyl-N'-ethyldipyrazolanthrone,N-nionocyclohexyldipyrazolanthrone, and The products described in U. S.1,804,531, and the like.

Polynuclear peri-di-and tetracarboxylic acid imides and irnidazoles, i.e. vat dyestuffs containing one of the radicals l l a 0 0 such asNaphth0ylene-( 1,8,4,5 bis-benzimidazoles,Perylene-3,4,9,10-tetracarb0xy1ic acid bis-alkylitnides, i. e.:Pery1ene-3,4,9,IO-tetracarboxylic acid bis methylimide,Perylene-3,4,9,10-tetracarboxylic acid bis-ethylimide,Perylene3,4,9,10-tetracarboxylic acid bis-butylimide,Perylene-3,4,9,10-tetracarboxylic acid bis-octylimide,

and the like, Perylene-3,4,9,IO-tetracarboxylic acid bis-arylimides, i.e.: Perylene-3,4,9,10-tetracarboxylic acid bis-p anisidide,Perylene-3,4,9,lO-tetracarboxylic acid bis-anilide,

Perylene-3,4,9,IO-tetracarboxylic acid bis-p-chloranilide,

Pery1ene-3,4,9,10-tetracarboxy1ic acid bis-p-toluidide,Perylene-3,4,9,IO-tetracarboxylic acid bis-o-anisidide, The heterocyclicimides and imidazoles disclosed in U. S. Patent Nos. 1,808,260,1,819,082, 1,836,529, 1,847,561, 1,856,711, 1,847,584, 1,878,986,1,888,625, 1,889,279, 1,910,465, 1,918,461, 1,924,090, 1,928,719,1,935,945,

1,952,661, 2,231,495, 2,543,747, and the like;

(11) Flavanthrone and the substitution products thereof such as itshalogenated and N-alkylated derivatives, i. e., N,N-dirnethylfiavanthrone,

6, l4-dibromofiavanthrone, 6,14-dichlorofiavanthrone, and the like;

(12) Pyranthrone (C. I. 1096) and its halogen, nitro, amino, alkyl,cyano, alkoxy, aralkoxy, aryloxy and a-royl derivatives, i. e.,

Chloropyranthrone (C. I. 1097),

Bromopyranthrone (C. I. 1098),

Iodopyranthrone (U. S. 1,863,987),

Highly halogenated pyranthrones containing more than 4 halogen atoms (U.S. 1,876,975), diniethylpyranthrone (U. S. 2,023,926), nitropyranthrone(U. S. 1,077,115), mono to tetra aminopyranthrones (U. S. 1,863,987),methoxy and ethoxy pyranthrones (U. S. 1,863,987), dimethoxypyranthrone(U. S. 1,906,231), dibenzoylpyranthrone (U. S. 1,906,231), and the like.

(13) Pyrenequinones, such as (14) Anthraquinone thioxanthones, such as1,2-anthraquinone thioxanthone,

4-amino-1,2-anthraquinone thioxanthone,

4-acylamino-1,2-anthraquinone thioxanthone,

4-benzoylamino-1,2-anthraquinone thioxanthone,

2 chloro 4 benzoylamino 1,2 anthraquinone thioxanthone,

B anthraquinonyl 4 amino 1,2 anthraquinone thioxanthone,

chloro 1,2 -anthraquinone thioxanthone,

4' chloro 1,2 anthraquinone thioxanthone,

2',5' dichloro 1,2 -anthraquinone thioxanthone,

3',4' dichloro 1,2 anthraquinone thioxanthone,

3,5-dichloro-1,2-anthraquinone thioxanthone,

5 methyl 1,2 anthraquinone thioxanthone,

5' methyl 4 -chloro 1,2 anthraquinone thioxanthone,

5'-methyl-4-phenylamino-1,2-anthraquinone thioxanthone,

Trianthraquinone-dithiooxanthone (German Patent No.

1,2,5,'6 dianthraquinone thioxanthone,

1,2,5,6-anthraquinone dithioxanthone.

The vat dyes of U. S. Patent Nos. 2,428,758, 2,428,759,

2,495,914, 2,533,170, and the like.

It is to be emphasized that ball mills and similar apparatus operatingby agitation, impact, and the like, are not suitable for producingapplicants desired results. In this connection, reference may be made toU. S. Patent No. 1,145,934 to Steindorfi et al. disclosing theconditioning of anthraquinone azines with as little as five times itsweight of sulfuric acid. The only milling or grinding process disclosedin the patent is in Example V wherein a mixture of 100 parts ofdyestufr' and 1400'- parts of acid are ground in a ball mill. It hasbeen found that the process of this example yields after filtrationofthe milled and drowned mixture, 9. presscake having a solids content ofabout 24.6 per cent by weight. This low' presscake concentration istypical of prior art methods of conditioning and is of courseunsatisfactory for practical commercial purposes. On the other hand, theprocess of this invention yields presscakes having solids contents of upto 60 per cent, the particles in the presscake being of such size, sizedistribution and surface characteristics as to render them exceedinglysuitable for standardizing for textile operations and the like.

The examples in the following table, in which parts are by weight unlessotherwise indicated, are illustrative of the instant invention and arenot to be regarded as limitative. In each of these examples, thedyestufi and sulfuric acid were introduced at room temperature into aWerner-Pfleiderer mill with agitation. The mass was then milled for thestated duration after which it was diluted by discharging into thestated amount of water under vigorous agitation. The slurry whichresulted was then filtered and the presscake washed acid free. In everyinstance, the presscake had a high solids content within a range of fromto per cent by weight, and was readily standardized to produce adyestuif composi tion having excellent application properties. It willbe readily understood that the dilution of the milled mixture with watermay alternatively be carried out by adding water and/or ice to themilled mixture instead of discharging the milled mixture into waterand/or ice.

Sulfuric Minutes Parts Ex. 100 parts Dyestufi Dura- Drowning PartsPercent tion Water Cone.

200 S0 15 2, 000 150 30 1, 500 300 96 10 3, 000 85 30 3, 000dlchloranthanthrone 150 100 60 l, 500 dlbromoanthanthrone 300 80 60 1,500 anthanthrone 150 100 60 1, 500 condensation product of anthanthroneand 800 80 60 1,500 l-arnino-anthraquinone (Ex. 6 S.

2,191,685). 9 2,7-d1metl1oxyanthanthrone 150 100 60 1, 500 10 beglflODJ]naphth [2,3-h1acridine-5, 8, 16 (15 H)- 200 100 30 2, 000

none. 11 10,12-dibromonaphth [2,3-0] acridine-5, 8, 14 200 100 30 2, 000

(13 H) -tri0nc. 12 6, 10, 12-trichloronapl1th [2, 3-0] acridine-5, 8,200 100 30 2,000

14 (13 H)-trione. 13 10, 12-dlbromo-11-cl1lornaphth [2, 3-01-5, 8, 14200 100 30 2,000

(13 H)-tr10ne. 14 benzo {1, 2-0, 4, 5-c'] djacridlne-fi, 9, 15, 18 (511,100 96 60 1, 000

14H)-tetrone. 16 do 1 100 80 60 1, 000 16 product of Example 2 100 96 601, 000 17 Indanthrene Blue R 150 100 60 1,500 18 do 300 80 60 1, 500 19Indanthrene Blue 250 96 30 2, 500 Indanthrene Blue 5G 250 96 80 2, 500Indanthrene Green BB. 250 96 30 500 l-amino1 2-anthraqulnonyl-2,3'-anthraquinone 100 96 60 1, 000

oxazo e. l-aminez-anthraquinony1-4'-ethoxy-2,3-an- 300 80 60 3, 000

thraqulnone oxazole. 4-amlnoanthraqulnone-1,2-(N)-phenyl oxazole 100 8060 1, 000 product of Example 3, U. S. 2,244,655 100 96 60 1,000 productof Example 9, U. S. 2,206,128-.. 100 96 60 1. 000 product of Example 1,U. 8. 2,174,072. 300 80 G0 3, 000 1,2,5,(S-anthraquinone-O-diphenyldlthiazola 100 30 1, 300 do 300 70 30 1, 300 3,4,3,4-benzidlne-C-diw-anthraquinonyl)- 200 96 60 2, 000

djthiazole. 1,2,5,G-anthraqulnone-C-di(2,4'-diehlor- 130 100 30 1, 300

phenyl)-dithiazole. Indanthrene Dark Blue BO 100 30 1, 500 IndanthreneViolet RT- 150 100 30 l, 500 Indanthrene Green B 150 100 30 1,500Indanthrene Violet R--- 200 96 00 2. 000 lndanthrene Brilliant Green B200 96 60 2,000 Indanthrene Green B 200 96 60 2, 000diarninodibenzanthrone (U. 8. 1,742,317 150 100 30 1, 500 4 it)-d%benzoylam ino-1,1' -d.lanthr1midecar- 150 100 15 1, 500

2.20 e. 40. 4,g dibenzoylamina-1,1-dianthrimidecar- 150 100 16 l, 500 ame.

Sulfuric Parts Minutes Drowning Ex. 100 parts Dyestufi Dura- Water PartsPercent tlon Cone.

Iii-dibenzoyl amino-1,1'-dianthrlmidecar- 150 100 1, 500

azo e. 1, 1',5'1"-tria11thrimlde-2,2-6,2-dicarbaz0le 300 80 60 3, 0001,2,1,2'-dianthraquinone carbazole 150 100 15 1, 500N,Ndimethyldlpyrazolanthrone 150 96 2, 000 N,N-d.iethyld1pyrazolanthrone 150 96 30 2, 000 uaphthoylene(1,8,4,5)bls-benzlmidazole. 200 96 30 2, 000 do 300 80 80 2, 000perylene-3,4,9,10tetracarboxy1ic acid bls-p- 150 100 15 1, 500

anisidide. peggelne-ml,9,10-tetracarboxyllc bls-p-methyl- 150 100 15 1,500

e. product of Ex. 2, U. S. 2,543,747--- 200 96 30 2,000 flsvanthrone 150100 30 1, 500 6,14-dlbromofiavanthrone 300 80 80 1, 500 pyranthrone 150100 30 2,000 do 300 80 30 2,000 chloropyranthrone 100 96 60 1,000bromopyranthrone 100 96 60 1,000 dlmethyl derivative of Ex. 4, U. S.2,023,926.-" 150 100 30 2, 000 3,4,8,9-dlbenzpyrenequinone-5,10 200 10060 2,000 3,4,8,9-dibenzpyrenequinone-5,10, dichloro de- 200 100 60 2,000

rlvative (U. S. 1,959,679). 3,4,8,9-dibenzpyrenequinone-5,10, dibromode- 200 100 60 2, 000

rivative (U. S. 1,952, 677). 3,4,8,9-dibenzpyrenequ1none-5, 10 300 80 303, 000 3,4-d.leh1oro-l,2-anthraquinone th1oxanthone 100 96 60 2,000 110250 80 60 2,000 product of Ex. 1, U. S. 2,428,758. 150 100 30 2, 000product of Ex. 1, U. S. 2,533,170- 100 96 00 2,000 Indanthrene Dark BlueBO 50 100 30 1, 000

In this example, 200 parts of 96% sulfuric acid were slowly added to themilled mass just prior to drowning.

This application is a continuation-in-part of applications Serial No.269,689, filed February 2, 1952; Serial No. 269,690, filed February 2,1952; Serial No. 279,941, filed April 1, 1952; Serial No. 272,689, filedFebruary 20, 1952; Serial No. 269,617, filed February 1, 1952; SerialNo. 253,212, filed October 25, 1951; Serial No. 254,636, filed November2, 1951; Serial No. 253,990, filed October 30, 1951; Serial No. 236,695,filed July 13, 1951; Serial No. 272,690, filed February 20, 1952; SerialNo. 236,696, filed July 13, 1951; Serial No. 236,697, filed July 13,1951; Serial No. 237,487, filed July 18, 1951, and Serial No. 254,813,filed November 3, 1951, all now abandoned. A

Various modifications and variations of this invention will be obviousto persons skilled in the art and it is to be understood that suchmodifications and variations are to be included within the purview ofthis application and the spirit and scope of the appended claims.

I claim:

1. A process comprising milling, by kneading, with forces predominantlyshearing in nature a mixture in the form of a doughy, kneadable masscomprising a Waterinsoluble vattable quinoidic compound and from 0.5 to4 parts by weight of the compound of a strong normally liquidnon-oxidizing, non-reactive acid having a concen tration ranging from 68to 100 per cent by weight, and then diluting the milled mixture withwater.

2. A process as described in claim 1 in which the acid is selected fromthe group consisting of sulfuric, chloroacetic, phosphoric,chlorosulfonic, and lower alkyl sulfonic acids.

3. A process as defined in claim 2 wherein the acid is sulfuric acid.

4. A process as defined in claim 1 wherein said quinoidic compound isselected from the group consisting of acylamino anthraquinones,anthanthrones, anthraquinone acridones, anthraquinone azines,anthraquinone oxazoles, anthraquinone thiazoles, dibenzanthrones,anthraquinone carbazoles, dipyrazolanthrones, polynuclear peridiandtetracarboxylic acid imides and imidazoles, flavanthrones, pyranthrones,pyrenequinones, and anthraquinone thioxanthones.

5. A process as defined in claim 1 wherein said quinoidic compound in anacylamino anthraquinone and said acid is sulfuric acid.

6. A process as defined in claim 5 wherein the acylamino anthraquinoneis Algol Yellow WG, the ratio of dyestuif to acid is 1:2 and theconcentration of acid is per cent.

7. A process as defined in claim 1 wherein said quinoidic compound is ananthraquinone acridone and said acid is sulfuric acid.

8. A process as defined in claim 7 wherein said anthraquinone acridoneis benzo[1,2-c,4,5-c']diacridine-6,9,15, 18-(5H,14H)-tetrone, the ratioof dyestuif to acid is 1:1 and the concentration of acid is 96 per cent.

9. A process as defined in claim 1 wherein said quinoidic compound is ananthraquinone thiazole and said acid is sulfuric acid.

10. A process as defined in claim 9 wherein said anthraquinone thiazoleis 1,2,5 ,6-anthraquinone-C-diphenyldithiazole, the ratio of dyestuft toacid is 1:3 and the concentration of acid is 70 per cent.

11. A process as defined in claim 1 wherein said quinoidic compound is adibenzanthrone and said acid is sulfuric acid.

12. A process as defined in claim 11 wherein said dibenzanthrone isIndanthrene Dark Blue BO, the ratio of dyestuif to acid is 1:15 and theacid concentration is 100 per cent.

13. A process as defined in claim 1 wherein said quinoidic compound isan anthraquinone carbazole and said acid is sulfuric acid.

14. A process as defined in claim 13 wherein said anthraquinonecarbazole is 4,4 dibenzoylamino 1,1 dianthrimide carbazole, the ratio ofdyestuff to acid is 1:15 and the acid concentration is 100 per cent.

Steindorfi et a1. July 13, 1915 Lang June 18, 1946 OTHER REFERENCESMattiello: Protective and Decorative 82-83, vol. 4, Wiley and Sons(1944).

Coatings, pp.

1. A PROCESS COMPRISING MILLING, BY KNEADING, WITH FORCES PREDOMINANTLYSHEARING IN NATURE A MIXTURE IN THE FORM OF A DOUGHY, KNEADABLE MASSCOMPRISING A WATER INSOLUBLE VATTABLE QUINOIDIC COMPOUND AND FROM 0.5 TO4 PART BY WEIGHT OF THE COMPOUND OF A STRONG NORMALLY LIQUIDNON-OXIDIXZING, NON-REACTIVE ACID HAVING A CONCENTRATION RANGING FROM 68TO 100 PER CENT BY WEIGHT, AND THEN DILUTING THE MILLED MIXTURE WITHWATER.